"Say My Name in Your Sleep" marks the first collaboration between Peters and fellow folk singer-songwriter
Marcus Mumford, with more confirmed to follow on
Florescence (2026). She recalled writing the song with Mumford at
Real World Studios in "deep winter" with "something magical and spooky in the air there", which she believed had translated into the sound of the track. As well as co-writing the track, Mumford also has co-producing credits and provided backing vocals. Australian singer-songwriter and frequent collaborator
Gretta Ray also provided backing vocals, as well as regular contributor
Ian Fitchuk co-producing. It was loosely inspired by the 1938 novel
Rebecca by
Daphne du Maurier, with CelebMix noting the "mature, literary-leaning sound" of the track. Peters added: "It's about having a tiny, secret sliver of your heart that still, deep down, hopes and prays they think of you – just a little, just when it's dark, just when they hear that song on the radio. It's about letting go, begrudgingly, but letting your shadow linger a moment too long." ==Credits and personnel==